Washington pleased to be in the First Lady’s favour

The 58-year-old actor was delighted to discover he is US First Lady Michelle Obama's secret celebrity crush and that she would love him to play her husband President Barack Obama in a movie about their lives, claiming he would take the role in a heartbeat.

However, the Oscar-nominated actor has one of the longest marriages in Hollywood to wife Pauletta and even worldwide icon Michelle setting her sights on him wouldn't tempt him to stray.

He added: "I've been married for 29 years - I'm not going anywhere."

Quizzed as to how his wife reacted when she found out he would be playing an alcohol and drug-binging pilot in Robert Zemeckis' new film, Denzel laughed: "I didn't tell her!"

The actor, who was joined by his co-star Kelly Riley on the red carpet, admitted he hadn't had a chance to explore London yet, but was keen to tuck into his favourite British snack after they finished promoting the film.

Asked if he had been exploring, he enthused: "No, but I'm going to have some fish and chips tonight. Salt and vinegar!"

Denzel might have to fend off stiff competition from Will Smith if he wants to play Barack in a biopic about his rise to power since the 'Men In Black' actor is convinced he would be the "natural choice".

Will previously joked: "It's about the ears, that's the thing. People see the ears and Barack and I both have the ears, so I'm the most natural choice.

"I told [Obama] jokingly, 'It's definitely something I would consider, you just have to write the ending.' So he's working on the ending right now."